/Engine/Source/Runtime/MovieSceneCapture/Public/FrameGrabber.h
Construct this frame grabber
FFrameGrabber ( [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [FSceneViewport](API\Runtime\Engine\Slate\FSceneViewport) > Viewport, FIntPoint DesiredBufferSize, EPixelFormat InPixelFormat, uint32 NumSurfaces )